Commission (LPC) considered designating the Warburg House a city landmark, which the Jewish Museum successfully opposed. The JTS continued to own the building in the 1970s, even as the seminary discontinued its funding of the museum. By April 1981, however, the LPC was again debating whether to preserve the Warburg Mansion as a city landmark. At the time, the museum wished to replace the List Building with a 25-story tower containing both museum space and apartments, which would require modifications to the Warburg House. The JTS again opposed designation, arguing that it would prevent the museum from modifying the mansion without the LPC's permission and significantly increase the cost of maintenance. According to the Seminary, the museum had an annual deficit of $200,000, and it needed another $500,000 to perform structural repairs to the Warburg House. Over 1,000 people signed a petition requesting the LPC grant landmark status to the Warburg Mansion. Manhattan Community Board 8, representing the surrounding neighborhood, voted in November 1981 to recommend that the LPC not designate the building as a landmark. Many local residents did not agree with this decision, and over 100 people wrote letters to the LPC supporting landmark protection. On November 24, 1981, the LPC designated the mansion as a city landmark; the designation excluded the List Building. The New York City Board of Estimate unanimously ratified the designation in April 1982, after the Jewish Museum submitted a modified plan for the tower, but the museum subsequently abandoned its plans for the tower project. The Warburg House was then added to the National Register of Historic Places on October 29, 1982. Expansion Jewish Museum director Joan Rosenbaum and philanthropist Dorothy Rodgers announced in June 1985 that they planned to expand the museum. At the time, the Jewish Museum had a collection of 14,000 objects, but the Warburg Mansion and the List Building could only accommodate a few hundred objects simultaneously. The museum briefly considered opening a satellite location. These plans were abandoned by May 1988, when Rosenbaum announced that the museum had hired architect Kevin Roche to design a seven-story annex north of the original building at a projected cost of $17 million. The LPC endorsed plans for the annex, which was to be designed in an identical style to the original mansion. Construction began in November 1990 and lasted two and a half years. The Jewish Museum agreed to relocate to